This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 12 |
| 6 | 36 |
| 7 | 118 |
| 8 | 411 |
| 9 | 1489 |
| 10 | 5572 |
| 11 | 21115 |
| 12 | 81121 |
| 13 | 314075 |
| 14 | 1224528 |
| 15 | 4799205 |
| 16 | 18896981 |
| 17 | 74695032 |
| 18 | 296275836 |
| 19 | 1178741568 |
| 20 | 4702507923 |
| 21 | 18806505243 |
| 22 | 75380203150 |
| 23 | 302754225098 |
| 24 | 1218239791106 |